Ubuntu 10.04 runs pretty bad out of the box on a Thinkpad T60. There was a lot of random screen flickering and the wifi connection would drop under heavy load. One way to make the wifi drop happen was to start watching a full episode of the daily show and then start copying a file over your network to your computer.
Thinkpad T60
ATI Radeon x1400
iwl3945
It seems the screen flickering has to do with the ATI drivers, which are really poor in linux. Surprisingly the wifi problems are related.
I found a post on the ubuntu forums detailing the fix. The fix is to turn off the kernal mode settings (KMS ). To do this edit your /etc/default/grub file and edit the contents:
sudo vi /etc/default/grub
# ORIGINAL: GRUB_CMDLINE_LINUX=””
GRUB_CMDLINE_LINUX=”nomodeset”
Follow this up with a sudo update-grub and reboot.
Also from the same thread it mentions you can also set kernal parameter radeon.modeset=0. I choose nomodeset, the option above which as worked for me.
Either nomodeset or more specific radeon.modeset=0 kernel parameter made it as responsive as 9.10 and fixed suspend and hibernate.
I also replaced NetworkManager with Wicd and am very pleased with it.
ATI Pink Flicker Bugs
Wifi Drop Bugs
WincenTech 